This invention relates to fluid seal systems, and more particularly to such seal systems involving a metal seal element that bears against a metallic surface to establish a metal-to-metal sealing interface preventing the passage of pressurized fluid.
The use of metal-to-metal seal systems for containing pressurized fluids is a time-honored and generally satisfactory practice in many fields. One field in which this practice has found considerable acceptance is the oil and gas industry, and especially in well drilling and completing operations. During these operations various well-head equipment is utilized to maintain control over the fluids and pressures encountered in the well, and where offshore wells are concerned the ability of this equipment to function in a reliable and safe manner is of paramount importance.
Fire is a dangerous potential at all oil and gas well sites, and because of the high cost of fire damage, particularly at offshore locations, and the increase in multi-well platforms at those locations fire-resistant well-head equipment is being specified on an escalating frequency. These factors have caused a corresponding increase in stringent standards for fire-resistant equipment, and efforts to comply with these demanding specifications have resulted in the invention described below.